and see today as a gift from god. Can the church say amen. Amen! ON THE MORNING OF JUNE 11th, The outpouring of support from my family, friends and colleagues, like dr. Rich besser, was overwhelming. They gave me the strength i needed as I prepared to share with the world news of a very personal nature. Sometimes treatment for cancer can lead to other serious medical issues and that is what I'm facing right now. It's something called mds. I didn't sleep the night before. Worrying how about going to be received. My big sister is a perfect match for me. And she is going to be my donor. She is going to be my donor. And I remember seeing diane and rich at the studio, and spending a little time with them before, making the announcement and you find of huddled today. Because for the longest time, it was just the three of us. Diane and I have been down this road before. When I battled breast cancer in 2007, she was the thelma to my louise. And I know it's been replayed. I can't watch it. I can't wait. Millions of viewers did watch and the reaction to my announcement of mds was beyond what I could ever have imagined. The day that I announced my diagnosis was also the day i began pre-treatment. You're gonna take a full deep breath in and hold your breath. So many questions. I decided to bring cameras along, because no matted what happened, I wanted to share my story. Physical exam, blood tests and chemo were relentless. Can't believe I'm doing this again to tell you the truth. It's different from the last time I had chemo. Which is longer and I lose my hair. I know this may be hard to believe, but even the painful bone marrow tests became routine. This is my fourth bone marrow test since april and it's um, you know. It's getting a little easier 'cause I know more of what to expect. Here comes the needle. You're going to feel -- one, two, three, pinch. Woo-hoo. Wait a minute, whoa, whoa wait a minute. This bone marrow test is over? Yes, we're 100% finished, and you did awesome. My oncologist dr. Gail roboz treats so many patients just like me. She certainly knew how to make this easier. My "gma" family and viewers also did everything they could to keep my spirits up. Here we are rocking the arm bands and here's why, because i know you've all been asking about them. It covers this, these two lines here. So it makes it easier to draw blood and also to administer medication like the chemo that I'm about to have. Now something I wasn't expecting, my colleagues and viewers turned my pic line cover into a fashion trend. So I started being sent these really wild little pic covers. It was funny how people were saying I was making a fashion statement. I'm like no I'm just trying to keep it clean. And there were a few viewers that were kind of disappointed after the pic line was taken out like "oh, I loved those pic covers. They were so pretty." And I'm like, "well, you know, you can have 'em." All along I was worried about my sally ann. Her tests and her fear of needles. But she and I want everyone around the country to know that being a bone marrow donor is a gift that you really can give. I had my ekg. I had my blood drawn. That's it? Oh, wow this is easy peezy. Are you scared? No, I'm not scad. I don't feel any fear about the procedure. I just totally trust that everything is going to work out as it should. &#9834; We need thee oh we need thee &#9834; oh, she's singing now. Get me out of here. Get me out of here! Just as I thought everything was finally in place for my transplant, my mom's health took a turn. My mother had suffered a stroke, the middle of july. And I was going home every weekend. And I don't care if you're 2, or 52, when you're sick, you want your mommy. You want your mommy. And she knew that. Tomorrow, robin will begin her journey as she takes her medical leave. August 30th was my final day on gma. My gma family, my family there at home. I love you and I'll see you soon. Dorothy sent a text, and she said, our mother is on her way home. That plane couldn't get there fast enough. Sally ann and I made it home in time to be by mom's side during her final moments. Mom made a cough, I got up and held her hand, and she turned, and -- it was her last breath. There's nothing like a mother's love. My beloved mother laid to rest. Now it was time for me to face the unknown road ahead without her here. It was time for the transplant. I remember seeing tears in dr. Giralt's eyes. things

This transcript has been automatically generated and may not be 100% accurate.

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